Buggy code:
public class bsController extends HttpServlet implements bsConstants { private static final long serialVersionUID = 1959097983289925130L ; private static log_init logInit ; private static db_init dbInit ; private static app_init appInit ; private static i_log_generator logG ; private static load_actions action_config ; private static load_message mess_config ; private static Object user_config ; private static load_authentication auth_config ; private static load_organization org_config ; private static load_menu menu_config ; private static String idApp ; private static ConcurrentHashMap local_container = new ConcurrentHashMap ( ) ; private static boolean reInit = false ; class LoaderConfigThreadProcess extends Thread { private boolean threadDone = false ; public LoaderConfigThreadProcess ( ) { } public void run ( ) { } } public void init ( ) throws ServletException , UnavailableException { } public void loadOnInit ( ) { } public static void resourcesInit ( ) { } public void reInit ( ) throws ServletException , UnavailableException { } public void service ( HttpServletRequest request , HttpServletResponse response ) throws ServletException , UnavailableException { } public static i_action getActionInstance ( String id_action , HttpServletRequest request , HttpServletResponse response ) throws bsControllerException , ServletException , UnavailableException { } public static i_action getActionInstance ( String id_action , String id_call , HttpServletRequest request , HttpServletResponse response ) throws bsControllerException , ServletException , UnavailableException { } public static i_action getPrevActionInstance ( String id_action , String id_current , HttpServletRequest request , HttpServletResponse response ) throws bsControllerException , ServletException , UnavailableException { } public static Object [ ] chech4AnotherOutputMode ( i_action action_instance , ServletContext servletContext , HttpServletRequest request , HttpServletResponse response , boolean allowAnotherOutput ) throws bsControllerException { if ( ( allowAnotherOutput && ( ( action_instance . get_bean ( ) ) != null ) ) && ( ( ( ( ( ( action_instance . getCurrent_redirect ( ) . get_uri ( ) ) == null ) || ( action_instance . getCurrent_redirect ( ) . get_uri ( ) . trim ( ) . equals ( "" ) ) ) || ( action_instance . get_bean ( ) . getXmloutput ( ) ) ) || ( action_instance . get_bean ( ) . getJsonoutput ( ) ) ) || ( ( ( ( ( action_instance . getCurrent_redirect ( ) . get_uri ( ) ) != null ) && ( ! ( action_instance . getCurrent_redirect ( ) . get_uri ( ) . trim ( ) . equals ( "" ) ) ) ) && ( ( action_instance . getCurrent_redirect ( ) . get_transformationName ( ) ) != null ) ) && ( ! ( action_instance . getCurrent_redirect ( ) . get_transformationName ( ) . equals ( "" ) ) ) ) ) ) { try { action_instance . actionBeforeRedirect ( request , response ) ; } catch ( Exception e ) { throw new bsControllerException ( ( ( ( "Controller<seq2seq4repair_space>generic<seq2seq4repair_space>actionBeforeRedirect<seq2seq4repair_space>error.<seq2seq4repair_space>Action:<seq2seq4repair_space>[" + ( action_instance . get_infoaction ( ) . getPath ( ) ) ) + "]<seq2seq4repair_space>->" ) + ( e . toString ( ) ) ) , request , iStub . log_ERROR ) ; } String output4SOAP = ( ( String ) ( action_instance . get_bean ( ) . get ( CONST_ID_OUTPUT4SOAP ) ) ) ; <START_BUG> String output4JSON = ( ( String ) ( action_instance . get_bean ( ) . get ( CONST_ID_OUTPUT4SOAP ) ) ) ; <END_BUG> byte [ ] output4BYTE = ( ( byte [ ] ) ( action_instance . get_bean ( ) . get ( CONST_ID_OUTPUT4BYTE ) ) ) ; if ( action_instance . get_bean ( ) . getXmloutput ( ) ) { if ( output4SOAP == null ) output4SOAP = util_beanMessageFactory . bean2xml ( action_instance . get_bean ( ) , ( ( action_instance . get_bean ( ) . get_infobean ( ) ) == null ? null : action_instance . get_bean ( ) . get_infobean ( ) . getName ( ) ) , true ) ; try { if ( ( ( action_instance . get_bean ( ) . getXmloutput_encoding ( ) ) != null ) && ( ! ( action_instance . get_bean ( ) . getXmloutput_encoding ( ) . equals ( "" ) ) ) ) response . getOutputStream ( ) . write ( output4SOAP . getBytes ( action_instance . get_bean ( ) . getXmloutput_encoding ( ) ) ) ; else response . getOutputStream ( ) . write ( output4SOAP . getBytes ( ) ) ; return new Object [ ] { response , Boolean . valueOf ( true ) } ; } catch ( Exception e ) { throw new bsControllerException ( ( ( ( "Controller<seq2seq4repair_space>generic<seq2seq4repair_space>redirect<seq2seq4repair_space>error.<seq2seq4repair_space>Print<seq2seq4repair_space>Bean<seq2seq4repair_space>as<seq2seq4repair_space>XML.<seq2seq4repair_space>Action:<seq2seq4repair_space>[" + ( action_instance . get_infoaction ( ) . getPath ( ) ) ) + "]<seq2seq4repair_space>->" ) + ( e . toString ( ) ) ) , request , iStub . log_ERROR ) ; } } if ( action_instance . get_bean ( ) . getJsonoutput ( ) ) { if ( output4JSON == null ) output4JSON = util_beanMessageFactory . bean2json ( action_instance . get_bean ( ) , ( ( action_instance . get_bean ( ) . get_infobean ( ) ) == null ? null : action_instance . get_bean ( ) . get_infobean ( ) . getName ( ) ) ) ; try { if ( ( ( action_instance . get_bean ( ) . getJsonoutput_encoding ( ) ) != null ) && ( ! ( action_instance . get_bean ( ) . getJsonoutput_encoding ( ) . equals ( "" ) ) ) ) response . getOutputStream ( ) . write ( output4JSON . getBytes ( action_instance . get_bean ( ) . getJsonoutput_encoding ( ) ) ) ; else response . getOutputStream ( ) . write ( output4JSON . getBytes ( ) ) ; return new Object [ ] { response , Boolean . valueOf ( true ) } ; } catch ( Exception e ) { throw new bsControllerException ( ( ( ( "Controller<seq2seq4repair_space>generic<seq2seq4repair_space>redirect<seq2seq4repair_space>error.<seq2seq4repair_space>Print<seq2seq4repair_space>Bean<seq2seq4repair_space>as<seq2seq4repair_space>JSON.<seq2seq4repair_space>Action:<seq2seq4repair_space>[" + ( action_instance . get_infoaction ( ) . getPath ( ) ) ) + "]<seq2seq4repair_space>->" ) + ( e . toString ( ) ) ) , request , iStub . log_ERROR ) ; } }

Fix:
String output4JSON = ( ( String ) ( action_instance . get_bean ( ) . get ( CONST_ID_OUTPUT4JSON ) ) ) ;